m-h lighting height

How high should a hqi 150 be over a 29 gallon,with 2" sand bed?

 

It depends on the conditions, I would say maybe 8-10 inches? That way it doesn't make your tank too hot.... some other people might even suggest higher than that. I have a 120 w/ 2 150w MH and they are about 4 inches off the water because I haven't had time to make a canopy yet.... I notice high temps and a lot of evaporation.

 

anywhere from 6-10 inches

 

Thanks for the quick respons,my first post

 

and,by chaning my bulb which is a phonix 14,000k.same just replace, Do i have to cut back hours ?

 

You could probably go with starting an hour later and turning off an hour sooner. It shouldn't cause too much of a problem though. Just raise the light when you first install it and maybe lower it an inch a week or something like that.